/Engine/Plugins/MeshPainting/Source/MeshPaintingToolset/Public/MeshPaintHelpers.h
Retrieves the Vertex Color buffer size for the given LOD level in the Mesh
uint32 GetVertexColorBufferSize ( [UMeshComponent](API\Runtime\Engine\Components\UMeshComponent) * MeshComponent, int32 LODIndex, bool bInstance )